1. Technical Field
The present disclosure relates to a color degradation compensation method, especially relates to a color degradation compensation method for a microscope image.
2. Description of Related Art
An image capturing device such as a microscope, a digital camera or a digital recorder essentially includes an optical lens assembly and an analog/digital converter (ex. CMOS or CCD senor). When a light is irradiated to an object, the light emitted from the object is captured by the image capturing device, and is transformed by the analog/digital converter so as to form a digital image readable by an electronic device. The light irradiated to the object is usually a white light, which is composed of several kinds of color lights. In a color system, three primary colors red, green and blue are utilized for generating different colors. However, different color lights have different optical characteristics such as wavelength or refractive index, etc. When different color lights pass through the optical lens assembly, chromatic dispersion will be occurred due to different focusing of each of the color lights, and the chromatic dispersion will form a chromatic aberration (color degradation) of the image. The chromatic aberration of the image will lead to obvious color shift between the edge area and the center area of the image. For example, a purple fringe occurred on the digital camera image; or a color shift between an edge and a center of the microscope image.
For solving the chromatic aberration of the image, conventionally, a hardware calibrating method or a software calibrating method is proposed.
In the hardware calibrating method, physical parameters such as curve radius, distance and shape of each lens element are modified for reducing the chromatic aberration. In the software calibrating method, an image processing procedure is utilized for calibrating the color values of each point of the image for reducing the chromatic aberration.
In the aforementioned calibrating methods, the hardware calibrating method requires high precision adjustments on each lens element of the optical lens assembly, thus a complicated process is produced, and a manufacturing cost is high. In the software calibrating method, although several image calibration software have been provided, however, different algorithms of each of the image calibration software leads to different calibrating effect.